The present invention relates to a semiconductor device and an AC resistance measuring system including the semiconductor device. For example, the present invention relates to a semiconductor device suitable for preventing an increase in circuit size, and an AC resistance measuring system including the semiconductor device.
A measuring device for measuring the body composition of body fat or the like measures an AC voltage obtained when an AC reference current is caused to flow through a measurement target, such as a foot, and calculates the AC resistance of the measurement target based on the measurement result. The body composition of body fat or the like is estimated based on the AC resistance thus obtained.
A technique for measuring body fat is disclosed in, for example, Japanese Unexamined Patent Application Publication No. H11-113872. A structure disclosed in Japanese Unexamined Patent Application Publication No. H11-113872 measures an AC voltage of a measurement target (an output voltage of an amplifier circuit) by using an AD converter.